If anything, I could see parks (such as CGA) open, but require guests to be vaccinated. I know that's been a bit of speculation, but it wouldn't surprise me if they opt in having the parks require at checkpoints; to show proof of vaccination before they continue further. It may be a measure to allow safety for the parks.
In the meantime, Cedar Fair had used the Knott's Twitter platform to spread their agreement to what CAPA has issued today.
Throughout the world, amusement parks have successfully reopened and there are no known COVID-19 outbreaks being traced back to parks.
reopencaamusementparks.com